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991.
992.
OBJECTIVE--To describe the human immunodeficiency virus (HIV) epidemic among socially and educationally disadvantaged young persons in the United States. DESIGN.-We analyzed demographic and geographic findings from the screening of Job Corps students for antibody to HIV. SETTING--The Job Corps is a federal training program for disadvantaged, out-of-school youth. POPULATION SCREENED--Residential students aged 16 to 21 years who entered the Job Corps from October 1987 through February 1990. MAIN OUTCOME MEASURE--Rates of observed HIV infection in entering students, stratified by demographic and geographic features. RESULTS--Of 137,209 Job Corps students screened, 488 were HIV seropositive (3.6 per 1000), a seroprevalence rate higher than that among military applicants of the same age. Overall seroprevalence was slightly higher in male (3.7 per 1000) than in female (3.2 per 1000) Job Corps students, but among those students aged 16 and 17 years, seroprevalence was higher among females (2.3 per 1000) than among males (1.5 per 1000) (P less than .05). For students aged 16 to 21 years, seroprevalence increased with year of age: 1.8 per 1000 per year for males and 0.7 per 1000 per year for females. Among those aged 21 years, HIV prevalence was 8.9 per 1000. For black and Hispanic students from large Northeastern cities, seroprevalence increased by 4.3 per 1000 per year of age and reached 24.8 per 1000 (one of 40) in students aged 21 years. However, among students from rural areas and small towns, HIV seroprevalence was disproportionately high in the Southeast. Compared with recently described US patients with the acquired immunodeficiency syndrome, HIV-infected students who entered the Job Corps were much more likely to be female. CONCLUSIONS--These findings show that disadvantaged, out-of-school adolescents are at high risk for HIV infection. The screening results identified surprisingly high seroprevalence in the southeastern United States and demonstrated a marked shift in the HIV epidemic to young women. Controlling the HIV epidemic among teenagers must include interventions that will reach adolescents early and outside of the formal educational system.  相似文献   
993.
OBJECTIVE.--To review our experience with lung transplantation, emphasizing recipient selection, choice of procedure, functional results, and outcome. DESIGN.--Retrospective review of patients who received lung transplants at Barnes Hospital, St Louis, Mo, between July 1, 1988, and January 31, 1991. SETTING.--Washington University School of Medicine, St Louis, Mo, and Barnes Hospital, a medical school and its affiliated referral hospital, respectively. PATIENTS.--Sixty-nine lung transplant procedures were performed in 66 recipients. Patients with clinically and physiologically severe lung disease were selected according to predetermined guidelines. Underlying diseases in the recipients included chronic obstructive pulmonary disease, alpha 1-antitrypsin deficiency emphysema, cystic fibrosis, pulmonary fibrosis, primary pulmonary hypertension, Eisenmenger's syndrome associated with an atrial septal defect, bronchiectasis, eosinophilic granuloma, and lymphangiomyomatosis. INTERVENTION.--Double-lung, bilateral sequential, and single-lung transplantations were performed. Eight patients underwent en bloc double-lung transplantations or a modification of this procedure with separate bronchial anastomoses. Thereafter, the bilateral sequential approach to replacement of both lungs was performed in 26 patients. Thirty-two patients underwent single-lung transplantations. MAIN OUTCOME MEASURES.--Pulmonary function tests, arterial blood gas levels, pulmonary artery pressure, pulmonary vascular resistance, and actuarial survival. RESULTS.--Actuarial survival at 1 year for the 66 lung transplant recipients was 79%. Actuarial survival at 1 year was 82% for the bilateral lung transplant recipients and was 90% for the single-lung transplant recipients. In patients with either restrictive or obstructive lung disease, pulmonary function tests and arterial blood gas levels improved markedly after lung transplantation. In patients with primary pulmonary hypertension or Eisenmenger's syndrome, the pulmonary artery pressure decreased and the cardiac index increased into the normal range after single-lung transplantation. CONCLUSIONS.--In carefully selected patients with end-stage lung disease, single-lung and bilateral lung transplantations can significantly improve functional capacity, with promising early actuarial survival statistics after 1 year.  相似文献   
994.
E B Larson 《JAMA》1991,265(23):3125-3126
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995.
To test the value of intensive management of diabetes before and during early pregnancy, 84 women recruited prior to conception were compared with 110 women who were already pregnant referred at 6 to 30 weeks' gestation. All underwent daily measurement of fasting and postprandial capillary blood glucose levels. Mean blood glucose levels during embryogenesis and organogenesis were within 3.3 to 7.8 mmol/L in 50% of preconception subjects and exceeded 10 mmol/L in 6.5%. One major congenital anomaly occurred in 84 infants (1.2%) of women treated before conception compared with 12 anomalies in 110 infants (10.9%) of mothers in the postconception group. Transient symptomatic hypoglycemia occurred during embryogenesis in 60% of women in the preconception group, with a median frequency of 2.7 episodes per week, but was not associated with excess malformations. We conclude that education and intensive management for glycemic control of diabetic women before and during early pregnancy will prevent excess rates of congenital anomalies in their infants.  相似文献   
996.
997.
Nuclear magnetic resonance (NMR) spectroscopy has been reported as an alternative method for quantitating deuterium oxide concentrations in the evaluation of total-body-water in humans. However, the presence of dissolved plasma proteins results in an underestimation of deuterium NMR (2H-NMR) intensity ratios, thereby causing an overestimation (5-6%) of total-body-water (TBW) values determined from nonsublimed patient plasma samples. We demonstrate that plasma samples must be corrected for the volume percentage of water in plasma. Correction of initial 2H-NMR intensity ratios with a factor of 0.93 results in intensity ratios comparable to those determined from plasma samples subjected to vacuum sublimation to remove all plasma solutes.  相似文献   
998.
999.
Electronystagmography (ENG) was performed on 127 dizzy patients and the findings were compared with the diagnosis obtained with a comprehensive neurological test battery. ENG was found to be abnormal in 49 (39%) of the patients: 19 with unilateral vestibular hyporeactivity, eight with directional preponderance, 12 with spontaneous or undirectional positional nystagmus, eight with abnormal smooth pursuit, and 13 with other abnormalities. Among the patients with abnormal ENGs, established central nervous system lesions were found in 28 cases (19 of these infratentorial lesions); nine peripheral vestibular lesions and five undefined vestibular lesions were found. Patients with normal ENGs showed fewer peripheral vestibular lesions and more dizziness of psychogenic aetiology. Almost half the patients with infratentorial lesions had normal ENGs. Patients with rotatory vertigo had fewer ENG abnormalities than those with other types of dizziness. These results suggest that ENG alone is of limited value in the diagnosis of dizziness. A comprehensive test battery is needed to establish the diagnosis.  相似文献   
1000.
The paper reviews existing reports on relations between pathologies leading to malabsorption and dental lesion in children. The following dental alterations are reported in the literature: delayed eruption of deciduous teeth, hypoplasia of enamel and dental caries. These lesions have been observed in gastrointestinal pathologies, for example, coeliac disease, chronic diarrhea and recurrent vomiting, intolerance of cow's milk protein, Crohn's disease and salmonellosis. The delayed eruption of deciduous teeth and hypoplasia of the enamel are certainly correlated to malabsorption and maldigestion, especially if these are protracted over time. Dental caries may be due to poor oral hygiene, poor diet and to the presence of modified calcification. Only a comparative study with a control group will enable the effective prevalence to be assessed.  相似文献   
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